Low voltage lighting power supply systems and methods

ABSTRACT

The present application discloses systems and methods for providing low voltage power for low voltage lighting sources, e.g., so-called landscape lighting. A low voltage lighting power supply includes an enclosure and a power circuit enclosed in the enclosure. In some embodiments the power circuit has a primary side and a secondary side. The primary side accepts power from a main power source and the secondary side has a plurality of separate output power circuits, each output power circuit generating a separate low voltage lighting power signal capable of lighting a plurality of low voltage light sources and each being rated for a particular output.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.15/358,679, filed Nov. 22, 2016 which is a continuation of U.S. patentapplication Ser. No. 14/532,493, filed Nov. 4, 2014, which claimspriority to and the benefit of U.S. Provisional Patent Application Ser.No. 61/899,564, filed Nov. 4, 2013, and also entitled “LOW VOLTAGELIGHTING POWER SUPPLY SYSTEMS AND METHODS” , the entire disclosures ofall three of which are all incorporated herein by reference as thoughfully recited herein.

BACKGROUND

The present disclosure generally relates to the field of low voltagepower supplies for low voltage lighting, for example landscape lightingsystems.

In such systems, a plurality of lights is often powered by a singlepower supply. The power supply supplies power evenly to all lights,regardless of whether the lights have differing power or currentrequirements and regardless of whether a user prefers differentbrightness for different sets of lights (e.g., front lights, backlights, mounted lights, etc.). Also, different sets of lights ondifferent power supplies easily lose synchronization and may turn onand/or off at different times even when the lights are intended to allturn on and/or off at the same time. Further, control of the lightsrequires use of a cumbersome interface on the power supply itself—if thepower supply even has such an interface and allows for such control.

It is also often difficult to add and remove new sets of lights from thepower supply. Typically, wires are run through PVC tubing in hole in thebottom of a landscape power supply. A large conduit nut secures the PVCtubing to the power supply's enclosure. The task of removing the nut andinserting and/or removing wires can be tedious. Moreover, it is oftendifficult for a user or technician installing such lights to determinehow many lights can be safely connected to the power supply withoutcausing an overload condition. Instead, a user or technician must engagein a time consuming trial and error process, and perhaps may even haveto replace fuses when an overload condition occurs.

SUMMARY

The present application discloses systems and methods for providing lowvoltage power for low voltage lighting sources, e.g., so-calledlandscape lighting. In one exemplary system, a low voltage lightingpower supply includes an enclosure and a power circuit enclosed in theenclosure. The power supply has a primary side and a secondary side. Theprimary side accepts power from a main power source and the secondaryside has a plurality of separate output power circuits, each outputpower circuit generating a separate low voltage lighting power signalcapable of lighting a plurality of low voltage light sources and eachbeing rated for a particular output.

An exemplary method of installing a lighting fixture includes observinga real time power-related parameter of a power supply to which thelighting fixture is to be connected, connecting the lighting fixture tothe power supply and observing the change in the real time power-relatedparameter of a power supply to which the lighting fixture was connected.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a high-level block diagram of an exemplary lighting system.

FIG. 2 is a high-level block diagram of another exemplary lightingsystem.

FIG. 3 is a high-level block diagram of an exemplary control system foran exemplary power supply.

Figs 4a 1-4 a 2, 4 b 1-4 b 2 and 4 c 1-4 c 2 are circuit diagrams forexemplary embodiments of a power supply.

FIGS. 5a-5b are isometric views of an exemplary power supply in closedand open states, respectively.

FIGS. 6a-6f are various views of an exemplary nozzle for the exemplarypower supply of FIGS. 5a -5 b.

FIGS. 7a-7b are further views of the exemplary power supply of FIGS. 5a-5 b.

DETAILED DESCRIPTION

This Detailed Description merely describes exemplary embodiments of theinvention and is not intended to limit the scope of the claims in anyway. Indeed, the invention as claimed is broader than the exemplaryembodiments, and the terms used in the claims have their full ordinarymeaning, unless an express definition is provided herein.

Referring now to FIG. 1, a block diagram of an exemplary lighting system100 is shown. The system includes a power supply 102 and a plurality oflight sources 104 a-104 f, e.g., LED light sources for outside use(so-called landscape lighting) or inside use (e.g., primary lighting,accent lighting, and/or undercabinet lighting). The power supplyincludes a control unit 106 and at least one power circuit 108 having aprimary side 110 and a secondary side 112. Optionally, the power supplyincludes a plurality of separate power circuits, each having its ownprimary side and secondary side, such as primary side 110 and associatedsecondary side 112 and primary side 114 and associated secondary side116. The primary side 110, 114 has a plurality of separate circuits,e.g., voltage converters, that accept power from a main power source andalter the main power to a form more suitable for the secondary side 112,116. The secondary side 112, 116 has a plurality of separate outputpower circuits, e.g., voltage converters, each output power circuitgenerating one or more separate low voltage lighting power signalscapable of lighting a plurality of low voltage light sources, e.g.,light sources 104 a-104 f, groups of which are sometimes referred to as“zones.”

In FIG. 1, secondary sides 112 and 116 are each shown generating twosuch separate low voltage lighting power signals, 120, 122, 124 and 126,capable of lighting a plurality of groups of low voltage light sources(“zones”). The entire power supply 102 and each power supply module,e.g., primary side 110, secondary side 112, etc., will typically berated for a particular power/current output. For example, the entirepower supply 102 may be rated for about 2.1 amps or about 360 watts andeach secondary side 112, 116 may be rated for about 6.67 amps or about100 watts, e.g., 7 amps×15 volts=105 watts. These exemplary numbersprovide only rough order of magnitude numbers for context and are notintended to be limiting.

In exemplary embodiments, primary side 110 and/or secondary side 112 arein the form of a separate module and primary side 114 and/or secondaryside 116 are in the form of a separate module. “Module” herein means aunitary piece that can be installed and/or removed as a whole unit,e.g., a plurality of components connected together via a circuit board.In an exemplary embodiment, each power supply module is rated for 100 W.On the primary side, the module will draw, in a worst case, 0.71 Amps(I_(in)=120 W/168V_(pk))→120 W since the module is specified to have atleast 80% efficiency under full load. Thus, a 300 LVPS system will drawI_(in)=0.71×3=2.13 Amps, and with a V_(in)=120*1.4=168 V_(pk) the systemwill draw roughly 360 W.

The exemplary power supply 102 has a power supply control unit 106having logic for controlling (e.g., turning off or on, limiting thecurrent of, reducing the voltage of, etc.) any one or more of primaryside 110, secondary side 112, primary side 114, and/or secondary side116. “Logic,” synonymous with “circuit” as used herein includes, but isnot limited to, analog hardware, digital hardware, firmware, softwareand/or combinations of each to perform one or more functions or actions.For example, based on desired applications or needs, logic may include asoftware controlled processor, discrete logic such as an applicationspecific integrated circuit (ASIC), programmed logic device, or otherprocessor.

“Computer” or “processor” as used herein includes, but is not limitedto, any programmed or programmable electronic device or coordinateddevices that can store, retrieve, and process data and may be aprocessing unit or in a distributed processing configuration. Examplesof processors include microprocessors, microcontrollers, graphicsprocessing units (GPUs), floating point units (FPUs), reducedinstruction set computing (RISC) processors, digital signal processors(DSPs), field programmable gate arrays (FPGAs), etc. Computer devicesherein can have any of various configurations, such as handheldcomputers (e.g., so-called smart phones), pad computers, tablet laptopcomputers, desktop computers, and other configurations, and includingother form factors. Logic may also be fully embodied as software.

“Software,” as used herein, includes but is not limited to one or morecomputer readable and/or executable instructions that cause a processoror other electronic device to perform functions, actions, processes,and/or behave in a desired manner. The instructions may be embodied invarious forms such as routines, algorithms, modules or programsincluding separate applications or code from dynamically linkedlibraries (DLLs). Software may also be implemented in various forms suchas a stand-alone program, a web-based program, a function call, asubroutine, a servlet, an application, an app, an applet (e.g., a Javaapplet), a plug-in, instructions stored in a memory, part of anoperating system, or other type of executable instructions orinterpreted instructions from which executable instructions are created.It will be appreciated by one of ordinary skill in the art that the formof software is dependent on, for example, requirements of a desiredapplication, the environment it runs on, and/or the desires of adesigner/programmer or the like.

In exemplary embodiments, any one or more of primary side 110, secondaryside 112, primary side 114, and/or secondary side 116 have powermeasurement circuitry (not shown in FIG. 1) that measures apower-related parameter for the power supply 102 or for that portion ofthe power supply 102. In exemplary embodiments, the power measurementcircuitry is a current sensor or other sensor capable of measuring inreal time a parameter indicating the power output of the power supply102 or that portion of the power supply to detect an imminent overloadcondition, which can damage the circuitry if maintained over seconds orminutes or weeks (depending on the degree of the overload condition).

“Real-time” and “real time” as used herein mean data that are used,stored, or transmitted for use or storage at the same time it is beinggenerated or promptly after it is generated. Real-time data should becollected and transmitted or displayed soon enough and often enough toinfluence a process accepting the real-time data as an input used by theprocess. In the context of this application, in exemplary “real time”embodiments for automatic control of the various power supply portionsby the control unit, it is expected that the power-related parameterwill be measured for use by the control unit at least every five (5)seconds and in exemplary embodiments the power-related parameter will bemeasured and transmitted or displayed at least every one (1) second ormultiple times per second, e.g., thirty (30) times per second. Incontrast, in exemplary “real time” embodiments for an installer usingthe circuits herein to facilitate installing light sources, it isexpected that the power-related parameter will be measured andtransmitted or displayed on a display at least every one (1) minute andin exemplary embodiments the power-related parameter will be measuredand transmitted or displayed at least every five (5) seconds or evenevery second or multiple times per second. In exemplary embodiments,each of the primary sides 110, 114 has such power measurement circuitryand each of the separate low voltage lighting power signals 120, 122 hassuch power measurement circuitry. “Automatic” and “automatically” asused herein mean without human intervention.

In exemplary embodiments, the power supply control unit logic includes aprocessor having a memory circuit with one or more non-transitorycomputer readable media of one or more data storage devices. As usedherein, “data storage device” means a device for non-transitory storageof code or data, e.g., a device with a non-transitory computer readablemedium. As used herein, “non-transitory computer readable medium” meansany suitable non-transitory computer readable medium for storing code ordata, such as a magnetic medium, e.g., fixed disks in external harddrives, fixed disks in internal hard drives, and flexible disks; anoptical medium, e.g., CD disk, DVD disk, and other media, e.g., ROM,PROM, EPROM, EEPROM, flash PROM, external flash memory drives, etc. Thismemory circuit might include flash memory (or other solid state memory)and/or RAM and/or ROM memories, and/or one or more fixed disk drivesand/or other memories. Memory circuits will have stored thereon logicmodules for performing the various functions and processes describedherein or a program to access such logic modules from a remote memory,such as a memory of access server (e.g., a browser program to accesssuch logic modules from the server memory).

In this example, the processor is preprogrammed to perform any one orany two or more of the following: (a) automatically compare the measuredreal-time power-related parameters to applicable thresholds and takeaction if the comparison indicates action is needed; (b) automaticallytake a power overload action in response to a comparison of one of themeasured power-related parameters to a threshold (indicating, e.g., anormal overload condition or a short circuit condition); and/or (c)automatically take a short circuit action in response to a comparison ofone of the measured power-related parameters to a threshold. Inexemplary embodiments, the low voltage lighting power supply has logicto take any one or any two or more of the following power overloadactions in response to the comparison indicating a power overloadcondition (e.g., a normal overload condition or a short circuitcondition): (a) automatically shut down the separate output powercircuit having the power overload condition, e.g., a primary side, asecondary side, or a portion of a secondary side; (b) automatically shutdown the separate low voltage lighting power signals having the poweroverload condition; (c) automatically shut down all the separate lowvoltage lighting power supply outputs; (d) automatically transmit amessage to a computer remote from the low voltage lighting power supply;(e) automatically reduce the voltage or available current of one or moreof the outputs of the separate output power circuit(s) having the poweroverload condition; (f) automatically reduce the voltage or availablecurrent of the separate low voltage lighting power signal(s) having thepower overload condition; (g) automatically indicate to a user that anoverload condition exists, e.g., via an audible alarm or a computerizedmessage displayed on a computer display; (h) shut down the primaryvoltage to the power supply unit having the fault condition; and/or (i)accept from a pre-programmed remote computer an instruction to performany of the foregoing. In exemplary embodiments, the specific one or morepower overload actions taken depends on a magnitude of differenceresulting from the comparison. For example, with an overload conditionthreshold of 105% of rated power being met, the control unit might bepre-programmed to take any of actions (a)-(i) above. Similarly, with ashort circuit condition threshold of 125% of rated power being met, thecontrol unit might be pre-programmed to take any of actions (a)-(i)above.

In exemplary embodiments, the low voltage lighting power supply has alight source installation mode in which the low voltage lighting powersupply helps the installer know in real time how loaded each separatelow voltage lighting power signal capable of lighting a plurality of lowvoltage light sources is (i.e., how loaded each “zone” is) so that asthe installer installs each light source, the installer has some idea ofwhether that separate low voltage lighting power signal is capable ofdriving one or more additional light sources that are to be installed.In exemplary embodiments, the low voltage lighting power supply displaysto an installer on a display of the low voltage lighting power supply inreal time the real-time measured power-related parameter measured on thesecondary side for a selected one or a selected two or more of theseparate output power circuits and/or for a selected one or a selectedtwo or more of the separate low voltage lighting power supply outputs.

In other exemplary embodiments, the low voltage lighting power supplytransmits (e.g., wirelessly transmits) to the installer in real time thereal-time measured power-related parameter measured on the secondaryside for a selected one or a selected two or more of the separate outputpower circuits and/or for a selected one or a selected two or more ofthe separate low voltage lighting power supply outputs. The transmissioncan be via any suitable wired or wireless medium or media, such as anyone or more of a Bluetooth signal, a low energy Bluetooth (BLE) signal,a Z-wave signal, an 802.15.4 (i.e., “Zigbee”), an 802.11 signal (WiFi),an NFC signal, a GPRS signal, a CDPD signal, a GSM signal, a UMTSsignal, a CDMA signal, an LTE signal, a WiMax signal, an infraredsignal, an ultraviolet signal, an acoustic signal, or some otherwireless signal. In the alternative, the transmission can be via a wiredmedium, such as via a power signal (e.g., X10 signals carried by theconductors for the power signal) or some other wired connection, such asone or more conductors back to the low voltage lighting power supply andconnected thereto via suitable connectors. In these examples, the lowvoltage lighting power supply may have corresponding communicationcircuitry and antennas, if necessary.

In exemplary embodiments, the low voltage lighting power supply in thelight source installation mode simply monitors in real time the one ormore real-time measured power-related parameters and indicates to theinstaller when one or more of the parameters is close to being at ratedpower but not yet overloaded, e.g., 90-99% of rated power, such as over95% of rated power. For example, the low voltage lighting power supplycan monitor in real time the real-time measured power-related parametermeasured on the secondary side for a selected one or a selected two ormore of the separate output power circuits and, in response to one ormore of the real-time measured power-related parameter measured on thesecondary side exceeding a threshold, indicating to an installer (e.g.,via audible alarm or by wired or wireless transmission) that the one ormore of the real-time measured power-related parameter measured on thesecondary side have exceeded a threshold that does not indicate a poweroverload condition.

In exemplary embodiments, the low voltage lighting power supplycomprises circuitry permitting unbalanced loading of a plurality ofseparate low voltage lighting power supply outputs that are output bythat separate output power circuit. For example, returning to FIG. 1,one zone 120 of secondary side 112 can use 5% of the power capability ofsecondary side 112 and the other zone 122 of secondary side 112 can use95% of the power capability of secondary side 112. Similarly, in FIG. 1one zone 124 of secondary side 116 can use 40% of the power capabilityof secondary side 116 and the other zone 126 of secondary side 116 canuse 60% of the power capability of secondary side 116.

In exemplary embodiments, the power supply 102 can be configured suchthat a power supply module and/or individual zones can be programmed tobe tuned on or off or dimmed via a remote computer 130 (e.g., a handheldcomputer running an app or a handheld remote control such as an AeonLabs Z-wave remote control) or remote sensors (e.g., Aeon Labs Z-Wavesensors, such as IR proximity sensors, door sensors, window sensors,etc.) or home control systems, e.g., a Z-wave Mi Casa Verde homeautomation controllers. The remote computer 130 may connect directly tothe power supply 102 via any of the suitable wireless or wiredconnections described earlier, or indirectly via another network ornetworks, such as Internet 132.

The power supplies can be controlled (e.g., turn on/off, programmed,etc.) via software executing on the computer 130, e.g., an app executingon a smart phone (e.g., an iPhone®) or a tablet computer (e.g., aniPad®) via any of the wired or wireless media mentioned above. Inexemplary embodiments, such software generates a graphical interface foradding light sources for control and controlling light sources. Thesoftware also transmits corresponding data to the low voltage lightingpower supply 102. In exemplary embodiments, such software performs anyone or any two or more of the following while adding light sources forcontrol:

(a) Provides a software user input (not shown), e.g., an icon or othersoftware user input with which the user can indicate a desire to add alight source or low voltage lighting power supply to be controlled bythat computer;

(b) Provides a software user input (not shown), e.g., one or morepull-down menus or drop-down menus, one or more icons or hyperlinks,and/or one or more select-one radio button sets, and/or select-all radiobutton sets, and/or one or more freeform text fields into which text canbe freely typed with a computer keyboard, with which a user can identifythe specific light source or the low voltage lighting power supply beingadded;

(c) Provides a software user input (not shown), e.g., one or morepull-down menus or drop-down menus, one or more icons or hyperlinks,and/or one or more select-one radio button sets, and/or select-all radiobutton sets, and/or one or more freeform text fields into which text canbe freely typed with a computer keyboard, with which a user can indicatewhether the computer is controlling a zone or an individual low voltagelighting power supply and enter a name for that fixture or the lowvoltage lighting power supply;

(d) Provides a software user input (not shown), e.g., one or morepull-down menus or drop-down menus, one or more icons or hyperlinks,and/or one or more select-one radio button sets, and/or select-all radiobutton sets, and/or one or more freeform text fields into which text canbe freely typed with a computer keyboard, with which a user can selector otherwise input an incremental brightness offset (such as apercentage) to increase or decrease the brightness of that low voltagelighting power supply or zone for one reason or another (e.g., tomanually compensate for power signal line losses or the age of lightsource);

(e) Provide a software user input (not shown), e.g., one or morepull-down menus or drop-down menus, one or more icons or hyperlinks,and/or one or more select-one radio button sets, and/or select-all radiobutton sets, and/or one or more freeform text fields into which text canbe freely typed with a computer keyboard, with which a user can selector otherwise input one or more power supply modules or zones of a powersupply for which the power supply is to display and/or transmit apower-related parameter, e.g., real-time current or power;

(f) Provides a software user input (not shown), e.g., one or morepull-down menus or drop-down menus, one or more icons or hyperlinks,and/or one or more select-one radio button sets, and/or select-all radiobutton sets, and/or one or more freeform text fields into which text canbe freely typed with a computer keyboard, with which a user can selector otherwise input one or more power supply modules or zones of a powersupply for which the power supply is to immediately turn off or on;and/or

(g) Provides a software user input (not shown), e.g., one or morepull-down menus or drop-down menus, one or more icons or hyperlinks,and/or one or more select-one radio button sets, and/or select-all radiobutton sets, and/or one or more freeform text fields into which text canbe freely typed with a computer keyboard, with which a user can add aremote control or remote sensor and select or otherwise input one ormore power supply modules or zones of a power supply for which the powersupply is to turn off or on or dim in response to the remote control orremote sensor.

In exemplary embodiments, such software performs any one or any two ormore of the following while controlling light sources and transmittingcorresponding data to the low voltage lighting power supply:

(a) Provides a software user input (not shown), e.g., one or morepull-down menus or drop-down menus, one or more icons or hyperlinks,and/or one or more select-one radio button sets, and/or select-all radiobutton sets, and/or one or more freeform text fields into which text canbe freely typed with a computer keyboard, with which a user can selectone or more low voltage lighting power supplies and one or more zones tocontrol;

(b) Provides a software user input (not shown), e.g., one or morepull-down menus or drop-down menus, one or more icons or sliders, and/orone or more select-one radio button sets, and/or select-all radio buttonsets, and/or one or more freeform text fields into which text can befreely typed with a computer keyboard, with which a user can turn on orturn off or control the brightness (voltage) of a low voltage lightingpower supply or zone such as inputting on or off or inputting abrightness value (e.g., a percentage) or a range (high, medium, low,off) or the like;

(c) Provides a software user input (not shown), e.g., one or morepull-down menus or drop-down menus, one or more icons or sliders, and/orone or more select-one radio button sets, and/or select-all radio buttonsets, and/or one or more freeform text fields into which text can befreely typed with a computer keyboard, with which a user canincrementally increase or decrease the brightness (voltage) of a zone oran entire low voltage lighting power supply with each actuation of thatuser input (and/or continuously increase or decrease the brightness(voltage) of a low voltage lighting power supply or a zone while theuser input is continually actuated);

(d) Provides a graphical display displaying to a user an indication ofhow brightly a selected low voltage lighting power supply or zone isbeing controlled, e.g., high, medium, low, or off or a specificpercentage;

(e) Provides a software user input (not shown), e.g., one or morepull-down menus or drop-down menus, one or more icons or sliders, and/orone or more select-one radio button sets, and/or select-all radio buttonsets, and/or one or more freeform text fields into which text can befreely typed with a computer keyboard, with which a user can select azone or power supply and clear a detected overload condition and causethe affected zone circuitry to become active;

(f) Provides a software user input (not shown), e.g., one or morepull-down menus or drop-down menus, one or more icons or sliders, and/orone or more select-one radio button sets, and/or select-all radio buttonsets, and/or one or more freeform text fields into which text can befreely typed with a computer keyboard, with which a user can select azone or power supply and clear a detected short circuit condition andcause the affected zone circuitry to become active again.

It is frustrating to have front lights on one power supply turn on fiveseconds after the back lights on a second power supply when they are allsupposed to turn on and off at the same time. In exemplary embodiments,exemplified by FIG. 2, two or more of the low voltage lighting powersupplies, e.g., power supplies 210, 220 and 230, having wireless orwired communication capability, synchronize lighting events, e.g.,turning lights 212 a-212 j, 222 a-222 j, and 232 a-232 j on at the sametime and turning them off at the same time. In exemplary embodiments,the plurality of low voltage lighting power supplies 210, 220 and 230use the communication medium to synchronize their real time clocks,e.g., periodically (such as daily) one of the low voltage lighting powersupplies transmits its RTC date, time, and geo-location settings to allthe others, which set their respective RTCs to that date, time, andgeo-location setting so that illumination instructions are carried outat the same time (whether based on absolute time of day or on sunriseand sunset calculated using geo-location settings). In the alternative,one power supply can simply transmit lighting event commands to theother power supplies wirelessly at the appropriate time for a particularzone or zones, e.g., turn on now or turn off now or perform sunriselighting activities now or sunset lighting activities now.

The exemplary implementations of a low voltage power supply generatedirect current (DC) constant voltage (e.g., 15 volts DC) outputs fordriving the light sources. FIG. 3 illustrates a high-level block diagramof one such exemplary system 300. As can be seen, a controller board 310is connected to an interface 312 that includes a display 314 and akeypad 316. The display 314 may be an liquid crystal display (LCD),light emitting diode (LED) array, or any other such suitable display.The keypad 316 may include any number of buttons, each of which may beassociated with one or more numbers, letters, or directions (e.g.,arrows). The display 314 may be positioned under a window proximate thekeypad 316. The controller board 310 accepts user input from the keypad316 and displays menus, data, etc. to users via the display 314.

The circuit board 310 includes one or two or more local power supplychips 322, for example model L78M05ABDT-TR linear voltage regulatorand/or model LP2950CDT-3.3RKG LDO voltage regulator. The circuit board310 also includes a pre-programmed processor 324, such as thePIC24FJ128GA008 microprocessor, a non-transitory (serial flash) memory326, such as model SST25VF010A-33-4I-SAE, and a non-transitory (serialEEPROM) memory 328, such as model AT25128AN. The circuit board 310further includes a voltage supervisor circuit 330, for example modelMCP1322-29, that keeps the processor in reset until the system voltagehas reached and stabilized at a proper level for reliable systemoperation. Also included is a wireless transceiver chip 332, for examplemodel ZM3102, with which the processor communicates back and forth withexternal devices, i.e., a Z-Wave® transceiver chip.

Figs 4a 1-4 a 2, 4 b 1-4 b 2 and 4 c 1-4 c 2 depict exemplary schematicdiagrams for an exemplary implementation of a two-zone DC power supplymodule with primary and secondary sides with a 100 watt total capabilityshared between the two zones. The power supply module includes a powersupply control chip 410, for example a model HR1000control chip, and atransformer 412 that steps down the voltage from the primary side andeffectively separates the primary and secondary sides. Two power supplychips 414 and 416 on the secondary side, which may be, for example,model MP6903DS chips, form an LLC converter with the other adjacentcomponents. Two outputs 422 and 424 (also labeled “VOUTA” and “VOUTB”respectively) are the two separate low voltage lighting power signalscapable of lighting a plurality of low voltage light sources (i.e., thelow voltage outputs for Zones A and B, respectively, for that circuit).Inputs 424 and 426 (also labeled “ENA” and “ENB” respectively) are usedby the processor to enable and disable the low voltage outputs for ZonesA and B, respectively, for that circuit. The processor driving inputs424 and/or 426 high causes output 422 to go HIGH (to source current tothe particular zone). The circuit further includes two current sensorchips 430 and 432, which may be, for example, model MP8110 chips, forthe low voltage outputs for Zones A and B, respectively, for thatcircuit.

In this exemplary embodiment, for each zone (separate low voltagelighting power signals capable of lighting a plurality of low voltagelight sources), the processor is programmed to turn off that individualzone if the power detected is greater than or equal to 105 watts, whichis an overload condition. Current is measured to calculate power basedon the constant 15 VDC output in these exemplary implementations. Inother exemplary embodiments, actual output voltage can be measured anduse to calculate power. An overload condition is cleared by removing theexcessive load (e.g., removing a fixture or fixtures or removing theobject causing the short circuit) and clearing the condition at theprocessor using a menu command at the display/keypad or other command,e.g., from a pre-programmed remote computer. For each of these zones(separate low voltage lighting power signals capable of lighting aplurality of low voltage light sources) the processor is programmed toturn off that individual zone if the power detected is greater than orequal to 125 watts (longer than a pre-determined delay to ensure thatthe 125 watts or greater is not due to inrush current), which is deemedto be a short circuit condition. A short circuit condition can only becleared using a menu command at the display/keypad or other command,e.g., from a pre-programmed remote computer. In this exemplaryembodiment, the processor does not monitor the primary side of the powersupply modules (as is done in other exemplary embodiments). Instead, theSMPS controller IC will turn the whole supply module off if ˜8 Amps isdrawn from the supply for short duration (long enough to not be mistakenfor in-rush and other such conditions).

FIG. 4c depicts an alternate embodiment of one part of theabove-described two-zone power supply module with primary and secondarysides. This circuit is functionally the same as the circuit discussedimmediately above, but instead uses a pair power supply control chips432 and 434, such as, for example, model LM5069 chips, to implement theinputs 426 and 428 instead of discrete components.

Referring now to FIGS. 5a and 5b , an exemplary enclosure 500 is shownin open closed and open states, respectively. The enclosure 500 has ahinged clam-shell design, which improves access to the wiring connectorsof power supply modules 502 a-502 c. As can be seen in the figures, akeypad 504 and display 506, as described earlier, are protected by ahinged outer cover 508. The power supply has three separate modularpower supplies 502 a-502 c(e.g., of the kind shown in Figs 4a 1-4 a 2, 4b 1-4 b 2 and 4 c 1-4 c 2), which can each be for example 100 watt powersupplies, each of which powers two separate zones that can unevenlydivide the 100 watts of power (note the three groups of four connectoropenings 510 a-510 c, one group at the bottom of each module, each grouphaving two connectors for each zone). The power supply modules 502 a-502c can be connected to the main power using any suitable connectors,e.g., flying leads on the individual power supply modules 502 a-502 care connected to conductors of the power cord 512 shown above via awire-nut.

The enclosure 500 features a nozzle 520 that helps with wire management.FIGS. 6a-6f show various views of the exemplary nozzle 520. The nozzle520 has a through-hole 522 and a flange 524 (in this embodiment theflange 524 is a circumferential flange going most of the way around)held in place by a groove 526 in the upper and lower enclosure portions500 (as seen more easily in FIG. 6e , with the nozzle 520 removed).Additionally, in this embodiment, the nozzle 520 is held in place in thegroove 526 by a snap catch 528 held by a tab 530 at the bottom of theenclosure 500 in which it is placed.

In exemplary embodiments, the through-hole 522 is shaped to accept alength of tubing, e.g., sized to be a friction fit for 1½″ trade sizeSchedule 40 PVC tubing, or any of a number of adapters, e.g., to stepdown the diameter to a small diameter PVC tubing. The nozzle 520facilitates assembly and installation of the power supply and associatedwiring by helping organize the wiring. For example, typical outdoorlandscape lighting installations include PVC tubing to hide all of the“home run” wires coming from the ground (buried) to the power supplyunit. During installation of the wiring, the nozzle 520 is detached fromthe enclosure 500 and removed from the groove 526. As an installerbrings a length of wire to the enclosure 500 for connection, theinstaller merely picks up the nozzle 520 on a length of tubing, threadsthe wire through the tubing and through-hole 522 of the nozzle 520, andconnects the electrical conductors in the wire to the connectors 510a-510 c for the appropriate zone. After all the wires are connected, theinstaller simply picks up the nozzle 520 and tubing (with all the wirestherethrough), guides the flange 524 into the groove 526 in the bottomof the enclosure 500, and snaps the catch 528 over the tab 530. Thewires are thus secured and out of the way, and the hinged cover 508 ofthe enclosure 500 can simply be closed without worrying about pinchingany of the wires between the two enclosure halves. This is much easierthat running the wires through the PVC tubing and the hole typically inthe bottom of a landscape power supply and then trying to install alarge conduit nut to secure the PVC tubing to the enclosure.

As can be seen in the images 7 a and 7 b, when the enclosure 500 ismounted on a vertical surface (not shown), the display 506 is angled atan angle of about ten (10) degrees (in alternate embodiments, about five(5) to about thirty (30) degrees) for ease of viewing the display 506and the keypad 504.

In exemplary embodiments, terminal blocks are mounted directly on theprinted circuit boards (PCBs). This is for manufacturability andreduction of parts. By attaching the terminal blocks directly to thePCBs, the typical design of having “jumper wires” from the PCB orwire-wound transformer is eliminated. These jumper wires are also oftena cause of field failure because they require periodic maintenance(tightening) that is not always done. By mounting the terminal blocks onthe PCB, the PCB can be angled to create better access for the installerto the terminal block openings.

In an exemplary method of installing a lighting fixture, an installermounts the enclosure, connects main power to the enclosure, e.g., viathe three-prong plug described above or by hard-wiring, uses the userinterface (e.g., keypad and menus or app on a remote computer) to turnon the power to a zone, uses the user interface to display the load onthat zone or all the zones, observes a real time power-related parameter(e.g., watts and/or amps) for that zone, connects the lighting fixtureto the zone of that power supply, and observes the change in the realtime power-related parameter of that zone. Thus, the installer can watchthe load on that zone steadily increase as fixture after fixture isadded until all of the fixtures are connected or the zone is too closeto its rated load to add any additional fixtures. If adding a lastlighting fixture to the zone causes an overload condition, a fixture isremoved and connected to a different zone. The user interface can beused to clear the overload condition, which is much more convenient thanhaving to replace a fuse or reset a circuit breaker of the main power.

Some of the steps, acts, and other processes and portions of processesare described herein as being done “automatically.” In the alternative,or in addition thereto, those steps, acts, and other processes andportions of processes can be done with one or more intervening humanacts or other manual acts that eventually trigger the mentioned step(s),act(s), and/or other process(es) and/or process portion(s).

While the present invention has been illustrated by the description ofembodiments thereof, and while the embodiments have been described inconsiderable detail, it is not the intention of the applicants torestrict or in any way limit the scope of the invention to such details.Additional advantages and modifications will readily appear to thoseskilled in the art. For example, many of the examples herein aredirected toward low voltage lighting, e.g., landscape lighting; much ofthe disclosure herein applies equally to other systems, such as 120 VACresidential and commercial lighting systems and 12 volt and 24 volt LEDtape light.

As another example, the steps of all processes and methods herein can beperformed in any order, unless two or more steps are expressly stated asbeing performed in a particular order, or certain steps inherentlyrequire a particular order. As yet another example, the power suppliesherein are shown and described as having a primary side and a secondaryside; other power supplies, e.g., battery-powered power supplies mightnot need a primary side per se. Instead, they have an output generatingcircuit generating a separate low voltage lighting power signal capableof lighting a plurality of low voltage light sources analogous to thesecondary circuits herein. The discussions herein and claims herein,with respect to a power supply secondary circuit, also apply to outputgenerating circuits without a primary circuit per se (which are alsoreferred to herein as secondary sides in the sense that they aresecondary to the main power source). Accordingly, departures may be madefrom such details without departing from the spirit or scope of theapplicant's general inventive concept.

What is claimed is:
 1. A modular low voltage lighting power supply,comprising: an enclosure having a cover, the enclosure housing aplurality of power supply modules that are accessible when the cover isin an open state and covered when the cover is in a closed state, eachof the plurality of power supply modules being installed into theenclosure and removed from the enclosure as a whole unit; and a controlunit enclosed in the enclosure, each of the plurality of power supplymodules in communication with the control module; wherein each of theplurality of power supply modules comprises at least one primary sideand a plurality of secondary sides, each secondary side generating a lowvoltage lighting power signal capable of lighting a plurality of lowvoltage light sources.
 2. The modular low voltage lighting power supplyof claim 1, wherein each of the plurality of power supply modulescomprises at least one primary side and a plurality of secondary sides,each secondary side generating a low voltage direct current (DC)lighting power signal capable of lighting a plurality of low voltagelight sources.
 3. The modular low voltage lighting power supply of claim2, where each secondary side is in communication with the control unitsuch that the control unit receives power-related parameters from thesecondary side.
 4. The modular low voltage lighting power supply ofclaim 3, where the control unit is configured to determine an availablecapacity of each of the secondary sides taking into account the loadsconnected to each respective secondary side.
 5. The modular low voltagelighting power supply of claim 2, where the control unit is configuredto determine an available capacity of each of the secondary sides takinginto account the loads connected to each respective secondary side. 6.The modular low voltage lighting power supply of claim 1, where eachprimary side is in communication with the control unit such that thecontrol unit receives power-related parameters from the primary side. 7.The modular low voltage lighting power supply of claim 6, where thepower related parameters are selected from a list consisting of current,voltage, and power.
 8. The modular low voltage lighting power supply ofclaim 6, where each secondary side is in communication with the controlunit such that the control unit receives power-related parameters fromthe secondary side.
 9. The modular low voltage lighting power supply ofclaim 8, where the control unit is configured to determine an availablecapacity of each of the secondary sides taking into account the loadsconnected to each respective secondary side.
 10. The modular low voltagelighting power supply of claim 6, where the control unit is configuredto determine an available capacity of each of the secondary sides takinginto account the loads connected to each respective secondary side. 11.The modular low voltage lighting power supply of claim 2, where eachprimary side is in communication with the control unit such that thecontrol unit receives power-related parameters from the primary side.12. The modular low voltage lighting power supply of claim 11, whereeach secondary side is in communication with the control unit such thatthe control unit receives power-related parameters from the secondaryside.
 13. The modular low voltage lighting power supply of claim 12,where the control unit is configured to determine an available capacityof each of the secondary sides taking into account the loads connectedto each respective secondary side.
 14. The modular low voltage lightingpower supply of claim 11, where the control unit is configured todetermine an available capacity of each of the secondary sides takinginto account the loads connected to each respective secondary side. 15.The modular low voltage lighting power supply of claim 1, where eachsecondary side is in communication with the control unit such that thecontrol unit receives power-related parameters from the secondary side.16. The modular low voltage lighting power supply of claim 15, where thecontrol unit is configured to determine an available capacity of each ofthe secondary sides taking into account the loads connected to eachrespective secondary side.
 17. The modular low voltage lighting powersupply of claim 1, where the control unit is configured to determine anavailable capacity of each of the secondary sides taking into accountthe loads connected to each respective secondary side.